Stringed instrument of the mandolin or guitar variety



G H. IRWIN AND F. A. MARTIN.

STRINGED INSTRUMENT OF THE MANDOLIN 0R GUITAR VARIETY- APPLICATION FILED IUNE30, I9I9.

1,355,977, Patented Oct. 19, 1920.

Inventors.

UNITED STATES PATENT OFFICE.

GEORGE HARTEORD IRWIN AND FREDERICK AARON MARTIN, OF LINDSAY, dN'IARIO, CANADA.

STRINGED INSTRUMENT OF THE MANDOLIN 0R GUITAR VARIETY.

Application filed June 30,

To all whom it may concern:

Be it known that we, GEORGE HARTFORD Irwin and FREDERICK AARON MARTIN, both subjects of the King of Great Britain, and residents of Lindsay, county of Victoria, Province of Ontario, in the Dominion of Canada, have invented certain new and useful Improvements in Stringed Instruments, of the Mandolin or Guitar Variety, de scribed in the following specification and illustrated in the accompanying drawings, that form part of the same. v

The objects of the invention are, to devise a simple form of stringed instrument which may be constructed comparatively cheaply, which will produce an exceptionally fine sound and which is susceptible of being altered by the change of the resonant diaphragm to produce loud or soft sounds, and further to produce an instrument which will project the sound very strongly in a definite direction.

The principal feature of the invention consists in the novel structure of instrument whereby a resonant diaphragm is placed over an orifice in a solid block structure and the strings are supported by a bridge arranged upon said diaphragm and the vibrations of the diaphragm are conducted through a sound distributing horn.

In the drawings, Figure 1 is a plan View of our improved construction.

Fig. 2 is a longitudinal sectional View through the instrument.

The instrument is formed from a solid board, being cut out to any desirable contour and here shown, more or less in the shape of a guitar and having the long neck 1 extending from-the broader body portion 2. A suitable finger board 3 is mounted on the neck 1. v

At the lower end of the body, the board is formed with a circular recess 4 having a small circular opening 5 extending through the center of the back thereof.

A diaphragm 6 is placed over the top of the recess 4 and the strings 7 are stretched over the bridge 8 which rests upon the diaphragm, holding it in place. The diaphragm is formed of thin wood or any other suitable resonant material and of a suitable thick- Specification of Letters Patent.

Patented Oct. 19, 1920.

1 919. Serial No. 307,694.

ness for the purpose desired. The vibration of the strings is transmitted to this resonant diaphragm and the vibrations are conveyed through the medium of the recess 4: and the central orifice 5 to a horn 9 secured to the back of the board.

The horn is formed of a narrow neck portion 10 curved to fit against the back of the instrument, while the mouth of the horn is secured to the back of the instrument adjacent to the neck.

An opening 11 is arranged in the board 2 the full diameter of the mouth of the horn and the sound vibrations produced in the diaphragm are conveyed through the horn and directed outwardly.

An instrument such as described is of very simple construction. It does not require the peculiar exactness of structure necessary to guitars, mandolins, violins, etc., but the diaphragms can be changed to produce the desired effect and such sounds as are produced upon the diaphragm are not dependent upon a whole vibrant body for the ultimate tone but are conducted directly from the diaphragm to the sound distributer, which may be formed of wood or metal as may be desired.

The structure is extremely simple and can be manufactured at very low cost. It will not deteriorate in the manner of other stringed instruments and various tone results may be produced therefrom by changing the diaphragms which are merely set in place and held by the bridge. It will also be possible to utilize skin diaphragms with this form of instrument as well as diaphragms of wood or other hard materials.

What we claim as our invention is 1. A stringed instrument, comprising, a flat board having a recess formed in the face thereof adjacent to one end and a small orifice leading from the center of the back of said recess. a flat resonant diaphragm covering the front side of said recess, a string supporting the bridge resting upon the diaphragm, an opening through the board, and a sound distributing horn secured to the back of the board and conveying the vibrations from the orifice at the back of the re cess to the opening through the board.

the board having a narrow neck portion communicating with the central orifice and having an enlarged discharge end and a 10 hole through the. board leading from the discharge end oi said horn.

GEORGE HARTFORD IRVIN. FREDERICK AARON MARTIN. 

